In response to Amato’s question, I did a quick Google search for how to cook brown rice, and I immediately learned about
First, the introduction to this way of cooking brown rice from the site above:
This way of cooking has been handed down since the Edo period in the Akita district.
This method, “bikkuri daki”, enables you to cook brown rice plump and soft just like white rice for relatively a short time.
You can use a normal pot, and you need not soak for a long time.
You can cook brown rice right away when you want to have some.
This method is very easy.
Sounds promising, does’t it? In the following description, the Japanese text will be omitted.
1. Get brown rice ready.
When cooked, 1 go (= 180 ml or cc) of rice will be equivalent to nearly 2 bowls (o-chawan) for adults.
2. Wash with water lightly.
You don’t have to soak for a long time.
3. You can use a normal pot like an enameled or stainless steel one.
A donabe is used here.
Add 1.2 to 1.5 times as much water as rice.
The older the rice, the more water.
4. Put on the lid, and heat on high heat.
If water boils over, lower the heat.
5. In about 15-20 min., the water will be reduced, giving off aroma.
If you are worried about whether the rice is scorched, you can take off the lid from time to time to check it.
6. When you hear sizzling sound, take off the lid, and add cold water.
The amount of water should be 0.8 to 1.2 times the rice.
“Bikkuri daki” is so called because you add bikkuri mizu (surprise water).
If you want to cook your rice soft, add more, and if you want to cook it hard, add less.
7. Stir well, put on the lid, and continue to simmer.
8. In 10 to 15 min., turn the heat to low, and then turn off the heat. (Note: The original Japanese text is vague here as to when to turn off the heat!)
9. Let stand for about 5 min.
10. Take off the lid, and mix well.
Edited to add: The third photo from the bottom of the site linked to above shows all of the 1 go of brown rice cooked with this method, while the second from the bottom shows all of the 1 go of brown rice cooked in a normal way. You can see the considerable difference in amount.